Network Management System and Method for Synchronization of Communication Network

1. A method of synchronizing a communication network, the method comprising: obtaining, by a network management system, a quality parameter of at least two or more synchronization sources connected to communication nodes in the communication network and a capacity parameter of the communication nodes connected to the synchronization sources; selecting, by the network management system, a synchronization source to be used for synchronization of the communication network from among the at least two or more synchronization sources, according to a priority calculated based on the obtained quality parameter and capacity parameter; and transmitting, by the network management system, a setting signal for setting the communication nodes in the communication network for synchronization of the communication network using a synchronization signal provided from the selected synchronization source.

2. The method of claim 1, wherein the quality parameter and the capacity parameter are stored in a form of a table in the network management system that manages the communication network.

3. The method of claim 1, wherein the priority is flexibly determined based on the quality parameter and the capacity parameter.

4. The method of claim 1, wherein the quality parameter is determined based on at least one of a holdover time of the synchronization source, temperature stability, an operating temperature range, a stratum level, a frequency quality, and a phase quality.

5. The method of claim 1, wherein the capacity parameter is determined based on a number of slave nodes that can be accommodated when a communication node to which the synchronization source is connected operates as a master node.

6. The method of claim 5, further comprising: receiving the capacity parameter from each of the communication nodes in the communication network.

7. The method of claim 1, wherein the priority is determined by reflecting a weight in each of the quality parameter and the capacity parameter.

8. The method of claim 1, further comprising: after selecting the synchronization source to be used for synchronization of the communication network, determining a synchronization mode of each of the communication nodes based on a selected synchronization source and characteristic information of each of the communication nodes in the communication network.

9. The method of claim 8, wherein the characteristic information of each of the communication nodes comprises: at least one of whether each of the communication nodes supports a specific synchronization mode, whether a communication node connected to a corresponding communication node may be tracked, a capacity of a slave node, a number of the communication nodes currently connected to a corresponding communication node, and a number of slave nodes corresponding to a communication node.

10. The method of claim 9, wherein the number of the communication nodes currently connected to the corresponding communication node is obtained using a connection tracking function of an IEEE 1588 Precision Time Protocol (PTP) protocol.

11. The method of claim 8, wherein the synchronization mode is a transparent clock mode or a boundary clock mode of an IEEE 1588 Precision Time Protocol (PTP) protocol.

12. The method of claim 1, wherein the communication network comprises at least one of a headend device, an extension device, and a remote device, and at least one of the synchronization sources is connected to the extension device or the remote device.

13. The method of claim 1, further comprising: monitoring whether the selected synchronization source has a failure; and selecting another synchronization source to be used for synchronization of the communication network according to a priority recalculated based on the quality parameter and the capacity parameter when the selected synchronization source has a failure.

14. The method of claim 13, further comprising: when the failure of the selected synchronization source is resolved, determining whether to use the selected synchronization source that was selected before the failure to synchronize the communication network.

15. A network management system comprising: a memory configured to obtain and store a quality parameter of at least two or more synchronization sources connected to communication nodes in a communication network and a capacity parameter of the communication nodes connected to the synchronization sources; a processor configured to select a synchronization source to be used for synchronization of the communication network from among the at least two or more synchronization sources, according to a priority calculated based on the quality parameter and the capacity parameter; and a communication interface configured to transmit a setting signal for setting the communication nodes in the communication network for synchronization of the communication network to the communication network by using a synchronization signal provided from the selected synchronization source.